Just installed the AP6-Pro and I’m impressed! Just hitting the same issue, no iOS here. It seems that untagged network blends in the VLANs. I run my WiFi network on seperate VLAN and it configured as untagged to the APs. My regular LAN is VLAN 10. When changing some settings clients get IPs from the untagged network. Also saw a few times that IPv6 Router Advertisements of the untagged network gets to the clients. So having from IPv6 configured. Best fix is to restart the AP. The SSID is WPA3 if that does matter.